1. Field of the Invention
The present invention relates generally to tools, receptacles, containers, and like systems directed to removing, used disposable surgical scalpel blades from scalpel handles and safely disposing of such contaminated blades.
2. Background of the Invention
Modern surgical scalpel blades are disposable, and fit to a reusable handle to thereby form a surgical knife. A typical commercially available surgical, or scalpel, blade has a sharpened tip and cutting edge at the forward portion of the blade and a shank extending to the rear portion of the blade. The scalpel blade has a variable width elongated central aperture, or slot, with its wider portion near the rear, or shank, and its narrower portion forward, near the blade. The shoulders of the central aperture between its wider and narrow portions act as detents.
The scalpel handle has an elongated boss, or tang, that is inserted into the aperture of the scalpel blade in order to mate with the blade and hold it during use of the surgical knife. The tang has a region of reduced thickness, and a forward-facing shoulder to this region, at its rear portion where it attaches to the scalpel handle. The front of the tang is typically rounded, and the shoulder of the reduced-thickness region is also typically rounded. The tang presents a groove on both sides.
In order to mount a scalpel blade, the front end of the tang is inserted into the wide part of the scalpel blade slot and the narrow portion of the scalpel blade slot slides in the tang's grooves until the rear of the scalpel blade's slot clears the rear of the shoulder of the reduced thickness region of the tang. The scalpel blade can then flatten, or snap, over the shoulder of the rear portion of the tang, locking the blade to the scalpel handle. In this position the rear of the scalpel blade slot is held by the shoulder on the reduced thickness region of the rear portion of the tang, which shoulder thus serves as a blade-retaining projection. The scalpel blade is held from moving further backwards on the tang by its aperture's detents, which engage a complementary feature on the tang.
To remove the scalpel blade from the scalpel handle's tang, the rear edge of the blade must be lifted away from the tang's shoulder so as to permit the handle to be drawn away from the scalpel blade. The tang must be withdrawn from the scalpel blade so that the groove, or undercut, portion of the tang becomes disengaged from the narrow portion of the scalpel blade's aperture.
The removal of a scalpel blade from a scalpel handle is problemsome, whether performed with general or specialized tools. A problem is presented when the rear, or shank, end of the scalpel blade is lifted away from the tang's shoulder. The bending torsion induced in the scalpel blade acts against the grooves of the tang, including at the location of the detents of the scalpel blade's central aperture. In sliding the scalpel blade along the tang's grooves the blade's detents, which are square-shouldered and square-cornered, scrape against the tang's grooves. This is especially true just as the narrower forward portion of the scalpel blade's apertures is about to be slid clear of the grooves. The scraping makes the sliding extraction of the scalpel handle from the scalpel blade require modest manual force, and to thusly be difficult of being precisely manually controlled. The sudden release of spring force when the bent scalpel blade is pulled clear of the grooves of the tang of the scalpel handle is similarly difficult of being precisely manually controlled. This difficulty in positively controlling a sharp and dangerous object is problemsome.
For example, it is possible to remove a scalpel blade from a scalpel handle by simple manual manipulations. The rear end of the slot of the scalpel blade is typically disengaged from the shoulder of the tang of the handle by using surgical forceps to grasp the blade. The blade is bent by the forceps and slid along the tang. The required bending of the blade causes the blade to snap upwards when it reaches the wide portion of its variable-width slot. This action is dangerous because control of the scalpel blade with the forceps may be lost, and the blade may fly through the air and cut someone. Even if the flying blade does not cause injury, is simply propelled away from the removal area, it spreads contamination. It may become temporarily lost, and will ultimately have to be retrieved.
Because of the high risk of exposing people to injury, infection, or disease by unsafe scalpel blade removal and handling until proper disposal can be made, members of surgical staff are reluctant to use forceps or hemostats to remove scalpel blades because, if their hands slip along the blade or if they lose control of the blade, they or other personnel may be cut. The recent outbreak of the highly contagious AIDS disease has further highlighted the need for a safe way of removing and disposing of used scalpel blades.
A number of previous scalpel blade removers and disposal devices attempt to deal with the requirement for safe removal and disposal of used scalpel blades. For example, U.S. patent Ser. No. 4,106,620 discloses the use of an internally notched retaining device for the dispensing of surgical scalpel blades. The surgical blade and the tang of the scalpel handle are inserted into a cavity of the device through a small hole. The handle is then manipulated, with some difficulty, so that the rear end of the scalpel blade slips between outwardly projecting ears of the retaining device. The handle is then manipulated to lift the rear portion of the tang away from the rear portion of the scalpel blade's aperture and to withdraw the tang from the scalpel blade's aperture.
A SCALPEL BLADE REMOVER AND COLLECTOR shown in U.S. patent Ser. No. 4,168,777 requires that the scalpel handle should be precisely aligned with the body of a blade removing/receiving device in order to ensure that the edge of the shank of the scalpel blade properly engages a flange which retains the blade as the scalpel handle is withdrawn.
U.S. patent Ser. No. 4,318,473 for a SURGICAL BLADE REMOVER AND DISPOSAL DEVICE likewise requires that, a tang mounting a scalpel blade having been inserted into a blade receiving/disposing device, the handle must be moved in order to bow the blade and to release a the blade from the tang so that the handle may be withdrawn.
Still another mechanism is taught in U.S. patent Ser. No. 4,746,016 for a BLADE REMOVAL AND/OR MOUNTING MECHANISM AND DISPENSER EXTRACTOR-DISPOSAL APPARATUS INCLUDING SAME. The mechanism includes a handle guide on one side of a passageway and an extracting means affixed on the opposite side of the passageway. The handle guide permits deflection of the handle for withdrawal of the tang out of a mating relationship with the elongated slot of the scalpel blade, which is retained within the mechanism by the blade retaining means.
The previous mechanisms that act to remove a scalpel blade from a scalpel handle by sticking the blade mounted upon the handle's tang into a cavity and by subsequently maneuvering the handle in order to dislodge the blade do not work well because of the forces required, and because of the nonspecific and uncontrolled nature of the force application. This limitation on this class of previous devices is, to some extent, obvious. A scalpel blade mounted to a scalpel handle is intended to be inserted into bodily cavities, including into bone, without coming loose from the handle. Although the various removal mechanisms that are directed to dislodging scalpel blades from scalpel handles exhibit internal contours that are more effective to so dislodge the blades from the handles than are bodily cavities, they are generally inefficient and ineffective in operation.
Possibly because of the operative limitations of that class of prior scalpel blade removal devices wherein the scalpel handle is maneuvered to dislodge the scalpel blade, some scalpel blade removal devices employ moving parts to attempt to remove the scalpel blade from the scalpel handle.
For example, U.S. patent Ser. No. 4,386,457 shows an SURGICAL BLADE REMOVER-RECEPTACLE including a housing having an aperture. A scalpel blade attached to a tang of a scalpel handle is inserted into the aperture. The scalpel handle's tang is pressed downwards into a narrow notch in the wall surrounding the aperture so that the edges of the notch engage the shank of the scalpel blade, preventing it from being moved into the notch. If this was all that was used for attempting to separate the scalpel blade from the scalpel handle, than this particular remover-receptacle would be substantially similar to previous devices. However, two spring-loaded pinch members extend from within the aperture. These pinch members are pinched together by the finger of a user so as to engage the proposed edges of the blade, effectively preventing it from moving as the scalpel handle is disengaged from the scalpel blade and pulled away from the remover-receptacle. When the pinch members are released, the blade falls to the bottom of the interior of the housing, which serves as a receptacle.
Likewise, U.S. patent Ser. No. 4,730,376 for a BLADE REMOVAL APPARATUS FOR CHANGEABLE BLADE SCALPEL shows a box having a receptacle for a scalpel blade mounted to a scalpel handle. When the scalpel blade on the handle's tang is located within the box, a pair of projection pieces on the box force the blade surface located on both sides of the blade away from the undercut grooves of the handle's tang, thereby permitting the handle to be withdrawn. This forcing of the scalpel blade may induce by some movement of the scalpel handle (which is supposed to be fixedly held but is difficult to so hold), thereby permitting an undesirable uncertainty and variation in the extraction process.
This second class of previous scalpel blade removers are still generally characterized by the application of force between the scalpel blade handle, which is held in the hand, and the scalpel blade remover. In this manner, all the previous scalpel blade removers are simply substituting for the forces that were previously applied by forceps or hemostats.
The present invention will be seen to be considerably different. A scalpel blade attached to a scalpel handle will be seen to be inserted within the aperture of a removal/disposal device. Once so inserted, however, no forcing of the handle is required. Indeed, the scalpel blade will be removed from the handle so adroitly that the handle will simply fall away from the remover by force of gravity should the remover and handle be so spatially oriented This type of positive, certain, and controlled application of force is alien to the previous scalpel blade remover devices.
In another matter, there is a requirement of accountability of surgical instruments to ensure that none remain within the patient after surgery. It is desirable that, after removal, a used scalpel blade should be placed in a disposal unit that permits, and preferably supports, that an accounting can be made of the number of disposed blades which, when added to the number of unused blades, should equal the number of new blades brought into the surgery. U.S. patent Ser. No. 4,013,109 discusses some of these requirements.
Insofar as is possible, it is desired that the disposal apparatus for scalpel blades should facilitate, and not merely not impede, the accountability requirement. One good way of doing so would be to make it very difficult that the number used scalpel blades should be in any way miscounted by making it absolutely unambiguous as to the location of each and every such used blade.
Finally, a scalpel blade disposal apparatus should present a mechanically and biologically sound container for the necessary handling and transport, and ultimate disposal, of a biologically contaminated article. Along these lines, it is desired that the scalpel blade, or any biological contaminants thereon, should not readily be able to exit the disposal apparatus at any time during or after the disposal process.
Nonetheless to meeting all these requirements, it is desirable that a scalpel blade remover should be simple and fool proof in operation by people of all levels of strength, training, and prior familiarity with the remover and its operation. The remover should preferably reinforce its correct operation without permitting any substantial possibility of misuse Finally, a scalpel blade remover would preferably be inexpensive in construction, and completely disposable.